1. Field of the Invention
The present invention relates to an object, a method, or a manufacturing method. In addition, the present invention relates to a process, a machine, manufacture, or a composition of matter. In particular, the present invention relates to, for example, a semiconductor device, a display device, a light-emitting device, or a manufacturing method thereof. In particular, the present invention relates to a method for forming projections and depressions, a sealing structure, or a light-emitting device. In particular, the present invention relates to a method for forming a substrate whose surface has projections and depressions, a sealing structure including a space surrounded by a substrate with projections and depressions, a sealing substrate, and a sealant for bonding the substrates, and a light-emitting device including a sealed light-emitting element.
2. Description of the Related Art
A substrate whose surface has projections and depressions is used for a variety of devices. The substrate whose surface has projections and depressions can be used as, for example, a diffusion plate of a light-emitting device.
Functions of some functional elements are impaired because of impurity diffusion. In order to maintain the functions of such functional elements, the following invention is known (Patent Document 1): a functional element is sealed in a space surrounded by a substrate provided with the functional elements, a sealing substrate, and a sealant for bonding the substrate and the sealing substrate.    Patent Document 1: Japanese Published Patent Application No. 2007-200835